The toddler’s face is glowing green from the tablet in her hands, which shows a cartoon boy singing a nursery rhyme and dancing with dinosaurs. The toddler doesn’t know what dinosaurs are or what the lyrics mean, but she’s so entranced that she doesn’t blink when her mother calls her name. “It’s literally like crack for her,” says her mom Meng Zhou at their home in Redwood City, Calif.

“It” is CoComelon, which may be the most streamed children’s entertainment program in the world. The show was watched for 33 billion minutes last year, more than the Netflix hits Squid Game and Bridgerton combined, according to market-measurement firm Nielsen. CoComelon had 3.6 billion views on YouTube in January, according to Tubular, a social-video measurement company, as many as three-quarters of whom were from outside the U.S. CoComelon was a Top 10 show on Netflix for more than 100 straight days in 2021, and its music is streamed 1.3 million times a day on Spotify.

CoComelon is not only a ratings juggernaut. It’s also a model for a new approach to children’s TV. The educators who developed hits like Sesame Street and SpongeBob SquarePants had to fight for years to get their shows on the air. A room of adults could toil on a concept that helped kids learn important ideas, only to find out viewers weren’t interested. CoComelon is part of a push to eliminate such guesswork. Its parent company, Moonbug Entertainment, scours digital platforms like YouTube for popular kids’ programming, buys them, and then tries to build them into even bigger phenomena, drawing on data from YouTube to figure out what resonates with audiences. “Data is really at the heart of everything we do,” says Richard Hickey, Moonbug’s head of creative. “With YouTube, you’ve got an audience there that literally tells you whether they want to watch something or not, in real time.”

Read More: How Ryan Kaji Became the Most Popular 10-Year-Old in the World

It’s not entirely clear how much of CoComelon’s runaway popularity stems from this formula and how much it owes to the pandemic, which put more kids in front of screens. As parents juggled childcare and remote work, demand for kiddie content spiked 52% between January 2020 and February 2022, according to data from Parrot Analytics. Either way, the success of the show is attracting big money. In November, Moonbug was acquired for $3 billion by two Disney alums backed by the private-equity firm Blackstone. Since then, the company has rolled out a CoComelon live tour, a Spotify podcast, and just about every form of merchandise you can imagine, from bubble machines to throw pillows.

Both parents and programming executives say there is something rare about the hold that CoComelon exerts on babies and toddlers. You can see the proof in the dozens of TikTok videos showing kids who hear the marimba tones of its theme song and come running. Zhou’s daughter’s third word, after Mama and Dada, was CoCo. “I don’t think we’ve ever seen anything like it when it comes to generating kids’ streaming audiences,” says Brian Fuhrer, senior vice president at Nielsen.

As the show and others like it become inescapable, parents are going to have to grapple with whether this type of children’s programming works for their families. Sure, their kids may love it—but does that mean it’s any good for them?

In a Los Angeles conference room, CoComelon executives are debating a pacifier. Seated around a white table strewn with open MacBooks, they’re reviewing a soon-to-be-released episode focused on a character named Cody, a classmate and best friend of JJ, the show’s cartoon protagonist.

The episode covers a rite of childhood: welcoming a younger sibling. Cody’s parents haven’t told him they’re having a baby. But as Cody and JJ sleuth around Cody’s home—singing an original song about solving an mystery, to the tune of “Teddy Bears’ Picnic”—they find a onesie, a rattle, and finally a pacifier, all objects that Cody has outgrown. An earlier version of the episode had Cody scorning the pacifier, saying it was “for babies.” But since the show is geared for children as young as 1, that sent the wrong message, Katie Nahab, a creative executive, explains to her colleagues. “Babies watch CoComelon, and they’re going to be looking at this and thinking, Oh, I shouldn’t want a pacifier, Cody doesn’t want a pacifier,” Nahab says. The script changed.

Considering the needs of babies is a new thing in kids’ TV. Before screens were ubiquitous, most families had just a television or two, and children’s shows were geared toward a broad age group. (Sesame Street, for instance, was targeted at 3-to-5-year-olds but watched by a wider spectrum of kids as well as their parents.) When parents started having phones in their pockets, entrepreneurs realized they could make shows for even smaller kids and still get millions of viewers.

CoComelon was created in 2005 by Jay Jeon, a father of two in Southern California. Jeon, who had directed some TV commercials, was trying to teach his kids the ABCs. He started working with his wife, a children’s-book author, to make videos to accompany the nursery rhymes they sang to their sons. They began uploading the cartoons to YouTube the following year under the brand name ABC Kid TV.

Over time, the revenue from YouTube ads allowed Jeon to quit his job to focus on the show. In 2017, he made two key adjustments: building the show around JJ, a toddler with a single blond curl, and changing the format from 2-D animation to 3-D. Monthly viewership on YouTube nearly doubled in two months, to 238 million views by December 2017, according to Tubular. By December 2018, CoComelon was getting 2 billion views a month.

In July 2020, Jeon sold his company, Treasure Studio, to Moonbug, which had been founded just two years earlier. Moonbug expanded the show to more audiences, inking deals with platforms in South Korea, China, and Europe. The company’s other big acquisitions include Little Baby Bum, a YouTube channel created by a British couple that revolves around nursery rhymes, and Blippi, a live-action YouTube show. The company is perpetually searching for the next sensation. In February, Moonbug acquired Little Angel, a network of YouTube channels featuring 3-D cartoons about a toddler named Baby John, who sings alongside his family as colorful subtitles play along the bottom of the screen.

For a company with this formula, CoComelon was a “once-in-a-generation opportunity,” Andy Yeatman, a Netflix alum who is the managing director of Moonbug, tells me. The show is deceptively simple. Each episode is a self-contained song that lasts two to three minutes. Some of them are nursery rhymes like “Wheels on the Bus”; others are original earworms about the moments that make up a toddler’s life. The songs star JJ and his two siblings, older brother TomTom and older sister YoYo; their mom and dad; and JJ’s friends. There’s a lot of repetition and an inordinate amount of disembodied toddler giggles. Some of the lyrics feel as if they were written by a computer that doesn’t quite get rhyming. (A sample: “Good, good, carrots are good for you/ Yay, yay, yay, I love them, ooh.”)

But there are little touches, experts say, that make the show appealing to younger kids in particular. The world depicted on CoComelon has bright colors and no sharp edges or corners. It is shot from a low perspective, so the viewer sees the world from a toddler’s level. The characters are unfailingly kind to one another; there is no conflict on CoComelon. And the topics are universal: viewers see JJ perform familiar tasks, like potty training and putting on shoes, and struggle with familiar challenges, like learning to share and getting sick. The show takes “every meaningful moment” in a toddler’s life and makes a song around it, says Patrick Reese, general manager of Moonbug.

Read More: The Best YA and Children’s Books of 2021

Every Monday, CoComelon puts out a new episode on YouTube, often experimenting with new characters, music, or story lines. Within the next few days, Moonbug’s data-insights team in London has crunched the numbers to suss out what did or didn’t work. If an element resonates, the creative team will try more of it. If it doesn’t, they move on to something else. The upshot is that viewers of Moonbug’s programs on platforms like Netflix are getting content that has already proved successful with a large audience.

One benefit of this iterative approach is that CoComelon can try a lot of different things quickly. Its episodes take 12 to 14 weeks to make, Reese says, which allows the show to respond to current events in ways that typical children’s programming, with its longer lead times, cannot. Early in the COVID-19 pandemic, CoComelon added an episode about handwashing; another segment focused on going to the doctor.

Lately the show has also introduced more characters of color. In addition to Cody, who is Black, there’s a Latina character named Nina Rodriguez, whose mom works as a firefighter. The diversity has helped CoComelon find new viewers: 56% of its audience comes from African American, Hispanic, or Asian American homes, according to Nielsen.

There are also downsides to a children’s show taking its programming cues from YouTube stats. If all content were driven by what YouTube viewers liked most, we’d be watching endless videos of dogs befriending cats. Shows like Sesame Street or The Electric Company have curriculums developed by pediatricians, says Dimitri Christakis, director of the Center for Child Health, Behavior and Development at Seattle Children’s Research Institute. They rely on metrics that show whether a children’s series is educational. While CoComelon may look that way to parents because it has words highlighted on the screen and tackles concepts like “left” and “right,” those ideas aren’t actually accessible to little kids in the process of learning language. “It’s one of those shows that is designed for parents to think they’re educational,” Christakis says, “but it doesn’t strike me as being high-quality at all.”

CoComelon execs say they send concepts and scripts to educational consultants who help verify whether an episode is too advanced for young kids and whether it will make them feel safe. The show tries to model good behavior so that kids and parents alike can see how a loving family would behave in an ideal world. “Developmentally, we want to make sure that we’re on point and that we’re hitting our core age demo” of 1 through 3, says Hickey, the Moonbug executive. Never mind that the American Academy of Pediatrics recommends no screen time for children under 18 months, unless it’s video chatting with a parent or family member. Most families threw those recommendations out the window in the hardest days of the pandemic and haven’t looked back.

In late 2021, a mom and former preschool teacher named Jerrica Sannes, who has a master’s degree in early-childhood curriculum and instruction—and a website that helps parents wean their kids off TV—posted an Instagram story claiming that CoComelon was “hyperstimulating” and made its young viewers experience symptoms of addiction and withdrawal. The charge resonated with parents suspicious of what made the show so irresistible to their kids. Many left comments vowing to turn off CoComelon for good. Others criticized Sannes for scaremongering.

Read More: Sesame Street Is Talking More Explicitly About Race—and Welcoming Two Black Muppets

Child-development experts say CoComelon is no more problematic than most other children’s TV shows. “It’s not that CoComelon is addictive,” says Susan Linn, the author of Consuming Kids. “It’s that just about everything on the web is designed to be addictive.” That design works; even before the pandemic, kids under 2 spent about 49 minutes a day on screens, according to Common Sense Media. “You’re setting up kids to start depending on screens for stimulation and soothing,” Linn says. “What we really want is for kids to be able to amuse and soothe themselves.”

Ultimately, the show’s success gets kids attached to an entity whose primary interest is selling them stuff. Since Moonbug acquired CoComelon, the show has been translated into 10 languages and has doubled the amount of content available. In addition to plush toys and sleepwear, parents can now buy CoComelon-branded booster seats, xylophones, books, snacks, and kitchens. Moonbug has a book deal with Simon & Schuster and licensing agreements with dozens of toy brands.

Many of those products will feature staple characters like JJ. But as the universe of CoComelon expands, the merchandising possibilities are endless. The new episode in which Cody learns he’s going to be a big brother will be followed by others, executives say, in which he helps his parents set up a nursery, watches his mom’s baby bump grow, and then sees the baby coming home from the hospital. The Moonbug team will be waiting to see whether it’s a story line YouTube viewers want to watch—and will surely have Cody’s baby-sibling dolls ready to go if so. In the meantime, a CoComelon live show is on its way to Boston; Rochester, N.Y.; and Akron, Ohio. True to form, Moonbug is asking the internet where it should go next. —With reporting by Julia Zorthian □

Contact us at letters@time.com.